Intake air-filter cleaning system



Feb. 6, 1945.

INTAKE AIR-FILTER CLEANING SYSTEM Filed June 30, 1943 2 Sheets-Sheet -l jg K\ 1 w Q N HEW 3 E I D K a m INVENTOR.

R. L. SKINNER I 2,368,787

Feb. 6, 1945. R. 1.. SKINNER INTAKE AIR-FILTER CLEANING SYSTEM 2 Sheets-Sheet 2 Filed June 30 1943 INVENTOR. @l jflzrzrzer Patented Feb. 6, 1945 UNITED STATES PATENT OFFICE IN TAKE AIR-FILTER CLEANING SYSTEM Ralph L. Skimier, Detroit, Mich. Application June 30, 1943, Serial No. 492,867

2 Claims.

The current invention pertains to features of betterment and gain in cleanable air-filters used in connection with the carburetor-intakes of internal-combustion engines and comparable structures, and, while the particular embodiments of the invention set forth in detail hereinafter include an edge-filtration type of air-filter, the improvements are not necessarily limited to such style of filter.

An outstanding and paramount object of the invention is to provide a means or system for periodically sending a flow of fluid under substantial pressure backwards through the filter for cleaning purposes, this pressure being developed and supplied by the engine itself.

An added aim of the invention is to provide a construction of the character referred to which is relatively simple in structure, which can be produced at comparatively small cost, and which functions with efliciency and reliability for the accomplishment of the specified objects.

To enable thoselacquainted with this art to understand the invention, both from its structural and functional aspects and advantages,

or rearwardly closed by a screw-threaded removable'plug 20,

, such cylinder [9 housing a hollow slidable plunger three desirable embodiments thereof have been illustrated in the accompanying drawings forming a part of this specification, it being understood that the various parts of the construction are not necessarily of properrelative size.

In the drawings:

Figure 1 shows one style of structure in section;

Figure 2 illustrates fragmentarily and in section a modified control-valve for actuation and government of the main-valve regulating the discharge of the fluid under high pressure from the storage-tank; and

Figure 3 presents a somewhat difierent style of structure.

Referring to the drawings, a portion only of one cylinder of an internal-combustion engine has been shown and designated ll, its head l2 being illustrated as supplied with a spark-plug l3 screwed into the usual threaded hole therethrough, the interior of the spark-plug being connected by a passage l4 through its wall and a pipe l5 to the interior of a pressure-chamber or storage-tank I 6, such pipe being fittedwith a springpressed, ball check-valve 11 opening toward the tank and closing toward the spark-plug and the interior of the cylinder H with which it connects through the passage 14.

A valve-block l8 has a cylindrical cavity I 3 open at one end but which opening is normally 2|, constituting a main-valve, ordinarily held to its inner limit'of travel by a coiled spring 22 bearing at one end against the inner surface of the head of the valve and pressing at its other end against the plug 20.

Chamber I!) of block l8 also has connected to it opposed, registered passages or ports 23 and 24 controlled by the position of the valve 2 I, port or passage 23 being connected by a conduit 25 to the interior of the pressure-tank l6, whereas passage or port 24 is joined tothe interior of the carburetor-intake conduit 26 above the carburetor, which is not shown, by a conduit 21.

The inside of conduit 26 is in communication with a telescopic, elongatable and contractible sylphon 28 by a conduit 29 and the movable endwall of the sylphon is, joined to a control-valve 3| reciprocatory in a cylindrical space 32 in block l8, such valve governing and controlling the opening and closing of the connection between the block's registered passages 33 and 34, the former being connected by a small pipe 35 to the interior of pressure-tank l6 while the latter connects with the cylinder is on that side of the head of valve 2| opposite that on which the spring 22 acts.

Upwardly or outwardly beyond the connections 21 and 29, the air intake conduit 26 is supplied with an air-filter, characterized as a whole 36, and including a housing or casing 31 open to the external atmosphere at 38, and an apertured division-plate 39 on which is mounted a plurality of filter-packs 4|, each composed of a plurality of washer-shaped, impregnated paperdiscs held in registration so that their interior passages are in communication through the platerapertures with'the conduit 26 while their exteriors are supplied with the impure air entering the chamber which houses them through the inlet 38.

The air drawn or sucked through this filter, known as an edge-filter, in that the filtering action occurs inwardly through the spaces between the superposed material of which they are composed, is discharged through the internal passages of the filter-packs formed by the registered apertures of the stacks or packs of discs and through the holes in the division-plate 39 into the carbureterintake 26 to become a part of the fuel-mixture brought about by the carburetor.

Inasmuch as suchfilters are well-known in discs, rather than through the I the art, further description thereof is deemed unnecessary.

As is illustrated, intake-conduit 28 has a coiled-spring-controlled butterfly-valve 42 normally yieldingly held in fully-open position, the upper half of the valve being located opposite the connection of conduit 21 with the air-intake 26, so that any fluid under substantial pressure passing from the former into the latter automatically rocks the valve closed and maintains it in that position so long only as such fluid-flow prevails.

While the engine is running, its explosionpressures in the cylinder I I, as distinguished from its compression pressures, build up a maximum fluid pressure, say 600 pounds per square inch or more, in the storage-tank I6, by the automatic intermittent openings of the check-valve, and such pressure is maintained in the tank unless the fluid is discharged therefrom, return of such fluid to the engine-cylinder being prevented by the closing of the check-valve.

So-long as the filter 36 is functioning efficiently and satisfactorily, the pressure builds up in tank I6 and when such pressure reaches its predetermined limit, no more fluid enters the tank because the pressure already therein prevents admittance.

When after continued use the external surfaces of the several filter-packs become covered or unduly clogged by the dirt removed from the air which has passed through them, such air impeding dust or dirt causes an abnormal increase in suction or sub-atmospheric pressure in the air-intake 26 by reason of its hindering the free breathing of the filter and, such augmentation of suction acting on the sylphon, slides valve 3I to open the ports 33 and 34 causing some of the high pressure fluid in the tank to enter cylinder I9 and slide valve 2| to open ports 23 and 24, thus efiecting a sudden discharge of fluid into intake 26 where it immediately closes valve 42 to preclude its passage to the carburetor and engine, the fluid flowing reversely through all of the fllter-packs blowing off their adhering dust and dirt and delivering it out of the intake 38.

The filter-packs having been thus quickly, automatically and effectively freed from their surface contaminants, the whole system immediately necessarily of itself returns to normal operative condition, valve 42 opening, 2 I closing and the tank being ready for automatic, intermittent recharging until the maximum pressure of its contents is attained, whereupon everything is ready for the next cleaning or purifying operation when that is necessary.

As is shown fragmentarily in Figure 2, a springpressed slide-valve 43 may be used, if preferred, instead of the sylphon-actuated valve illustrated and described, thi valve opening the ports ;33 and 34 when the suction applied through tube 44 is sufficient to slide it to open position. If necessary, a bleeder-port I43 to the external atmosphere may be provided.

In some instances, it is desirable to obtain the cleaning fluid or gas from a source other than the internal-combustion engine, and a structure incorporating such a feature is portrayed in Figure 3.

In such illustration, the elements which are the same as, or comparable to, those in the other figures have been supplied with the same reference numerals.

valves 3| and As is fully shown, in this example a readily demountable and replaceable steel-bottle H2, containing air under high pressure, is connected through a suitable pressure-regulating valve H1 or known type to a tube I I5 communicating with one end of a chamber I0l in the block IBI, the opposite end of the chamber by means of a pipe I02 connecting with the interior of the lowerpressure tank I0, a spring-pressed ball-valve I03 in the chamber IOI controlling such connection between the bottle and tank.

As is illustrated slide-valve I3I in cylinder 32 has a rod extension 23I in line with, and adapted to control the opening and closing of the ballvalve I03.

Under normal conditions with the air-filter fully and satisfactorily operative, the air-pressure in tank I6 is automatically maintained at the predetermined value by reason of the pressure-regulator In, the ball-valve I03 being open.

When, however, the filter becomes clogged and valve I3l and its rod 23] are automatically shifted to the right, valve I03 is closed during the discharge of air from tank I6 reversely through the filter to perform its cleaning function and as soon as the latter operation is completed the movement of valve I3I to the left opens the ball-valve and air from the bottle flows through the connection described to replenish tank I6 and to restore the normal pressure there- It will be appreciated, therefore, that the supply of needed air comes from the bottle H2 and when its contents have been reduced by such repeated replenishing operations, the bottle may be replaced by a fully charged one.

Those skilled in this art will readily understand that the invention as set forth in the appended claims is not necessarily limited and restricted to the precise and exact details of structure and function and that modifications and changes within reasonable limits may be resorted to without departure from the heart and essence of the invention and without the loss or sacrifice of any of its substantial benefits and advantages.

Those acquainted with this art will appreciate that the invention is not confined to use in connection with internal-combustion engines and may be used with convenience and satisfaction with pumps or other operative mechanisms.

. I claim:

1. In an air-fllter-equipped air-intake for an operative mechanism including an intake-valve to open and close said air-intake, a container for gas under pressure, a conduit to discharge gas.

from said container into said air-intake outwardly beyond said intake-valve to'cause such introduced gas to flow reversely through the filter to clean the same, and a conduit-valve normally closing said conduit, the novel combinationof means actuated by reduced air-pressure in said air-intake to automatically intermittently temporarily open said conduit-valve and means to close said intake-valve during each period of such gas discharge into said intake.

2. The novel combination set forth in claim 1 in which said intake-valve closing means is actuated by the gas delivered from said container into said intake. I

RALPH L. SKINNER. 

